Commonly, the payload on trucks is stabilised by the process of tying one end of a rope to one fixed point of the truck, extending the other end of the rope around the load, looping the rope about a fixed receiving point, then securely tightening the rope around the load by tying one or more hitch knots, also known as sheep shanks, back along the length of the rope. However, the jolting motion of the truck causes the load to exert a force against the rope, leading to a loosening of the grip of the knot. The risk of the load moving independently of the truck poses a foreseeable risk of danger. Furthermore, the knot itself may threaten to interfere with vehicles passing nearby. For instance the loop of the hitch knot normally extends some distance from the side of the truck when not properly concealed, and can attach to vehicles passing in close proximity.
Earlier Australian patent application no. 33,646/89 by the same applicant discloses a rope tying device having a rope fixing means, a tensioning means and a receiving means, the arrangement being such that a portion of the free end of the rope is fixed to the fixing means and the free end of the rope is passed around a first anchor site external of the device and then a portion of the free end of the rope downstream thereof engages on the tensioning means whereby the rope is maintained under tension and the remaining free end of the rope is passed around a second anchor site external of the device and then secured to the receiving means.
However, that invention suffers from the disadvantage that it cannot produce a triple hitch knot which exerts greater pressure upon the load, thereby adding to load stability. Furthermore, the invention of Australian patent application no. 33,646/89 requires that tying off of the free end of the rope be done on the device. The requirement for tying off on the device necessitates that a receiving means be present on the device which can add considerably to the weight thereof. The weight and size of the device should be kept to as low a level as possible, and a receiving means on the device is an unnecessary contributor of the weight because tying off can be done externally of the device.